Method and apparatus for reproducing images at a distance



Jan. 27, 1931'. P. CHALFIN ET AL METHOD AND APPARATUS FOR REPRODUCING IMAGES AT A DISTANCE File-d July 5,. 1928 5 Sheets-Sheet l INVENTORS.- mail@ @agi ,Banjul/zu@ L WITNES SES:

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Jan. 27, 1931` P. cHALFlN ET A| 1,790,038

METHOD AND APPARATUS FOR REPRODUCING IMAGES AT A DISTANCE Filed July 5, 1928 5 sheets-sheet 2 E111-:1- E f j.`

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METHOD AND PPARATUS FOR REPRODUCING IMAGES ATVA DISTANCE Filed July 5, 1928 5 Sheets-Sheet 3 MPA/F/EH 1 F LTE F/f. rm

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Jan. 27, 1931 P. CHALFIN ET AL METHOD AND'APPARATUS FOR R'EPRODUCING IMAGES AT A DISTANCE Filed July 5, 1928 :EllslEl WITNESSE:

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Jan- 27,` 1931- P. CHALFIN ET AL I 1,799,038'

METHOD AND APPARATUS( FOR REPRDUCING IMAGES AT A DISTANCE ATTORNEY,

Patented Jan. 27, 1931 Unirse STA PHILIP CHALFIN .AND BENJAMIN CHALFIN, OF PHILADELPHI, PENNSYLVANIA METHOD AND .APPARATUS FOR-REPRODUCING IMAGES AT A"DISTANCE Application filed July 5,

Our vinvention relates to a method and apparatus for producing the likenesses of objects at a distarce.

ln transmite lg and reproducing pictures and particularly in producing likenesses of moving objects at a distance from the transmitting station, it is essential that the receiving apparatus i be perfectly synchronized with the transmitting apparatus.

.The objects'ot our invention are to provide a method of automatically synchronizingthe moving parts of a receiving apparatus with the moving parts of a transmitting apparatus and to provide apparatus for utilizing this method.

This object is attained by dividing the likeness of the subject into a succession of points of light by means of oscillating elements; directing the points of light into a photo-electric cell to cause electric impulses to flow therefrom which vary in intensity in proportion to the lights and shadows of the subject;

causing a synchronizing impulse to low from the photo-electric cell per oscillation of each oscillating element; transmitting the impulses receiving and amplifyingthe impulses, directing a beam of light, Whose intensity is governed by the impulses received, into oscillating lenses whose oscillations are controlled by the synchronizirg impulses; and directing the light from the lenses upon a screen where the likeness Ais reassembled, due to the oscillations of the lenses. c

While our invention may be incorporated in sending and receiving apparatuses of either the Wireless or wire connected types and used for the transmission and reception of pictures and the like, it has been shown embodied in a televisor. for use in conjunction with a radio receiving set, and in trans- .mitting apparatus for use inconjunction with a radio broadcasting station.

In the drawings- Figure 1 is a diagrammatical'representation of a'radio transmitting apparatus in which an embodiment of our invention has been incorporated, A

` Figure 2 is a cross-section through the lens elements and the object glass, as indicated by line 2--2'on Figure 1,

i928. serial No. 290,35s.

Figure 3 an elevation of oneof the lens elements shown 1n Figure 1,

' Figure 4 an elevation of the otherlens element shown in Figure 1, and

Figure 5 a cross-section'through the lens of the element shown in Figure 4,

Figure 6 is a diagrammatical representation of a radio receiving apparatus in which our invention has been incorporated,

Figure 7 an outside elevation of a receiving surface or screen upolnwhich the likeness is projected,

Figure 8 an elevation of one of the lens elements shown in Figure 6,

Figure 9 a sectional plan view 4taken on line 9 9 on Figure 8,

Figure 10 an elevation of the other lens element shown in Figure 6,

' Figure 11 a cross-section through the lens of the element shown 1in Figure 10, as indicated by lines 11-11 on that figure, and

Figure 12 a diagrammatic drawing of a part of a moditied form of receiving apparatus.

Referring first to Figure 1, sounds received by the microphone 1 are amplified by an ampliier 2, modulated by modulator 3 and deliver-ed to the antenna 4 by transmitter 5. As this part of the apparatus is Awell known and forms no part of our invention, it willr not be described in detail.

An object glass 6, preferably consisting of a doubleconvex lens 7 and a meniscus 8, is mounted in the end of a light-tight box 9 which has its interior blackened to pre-vent reflection of stray rays of light. 1 An oblong oscillating lens element 10, having its axis of oscillation horizontahis mounted in a lighttight partition 11 in box 9 and anoblong oscillating lens elen'ient 12, having its axis of oscillation vertical, mounted in a light-tight partition 13 in box 9 with theaxes of oscilla/- feb tion of both lenses in alignment with the axis of the object glass.

Lens element l0 may consist of a lens holder 20 (see Figures 2 and 3), having a double concave lens 21 near oneV end and a double convex lens 22 near the other, andv a frame 23 in which the axle 24 of the lens `holder is pivoted. The 'lens holder may be swung in one direction by a magnet 25 which, when energized, will attract an armature 26 secured to axle 24, and in the opposite direction by a second magnet or by a spiral spring 27 having one end secured to the frame and the other end to the axle. In order to overcome any jerk which the magnet might impart and to insure uniform oscillation, a dash pot 28 may be mounted on the frame and have its plunger 29 hinged to an arm 30 secured to the axle.

Lens element 12 may have an oblong double convex lens 31 pivotally mounted in a frame 32 and provided With an armature 33, a. magnet 34, a spring 35 and a dash pot 36 which are constructed and function similarly to the corresponding parts of lens element l0. Lens 31 preferably has its side adjacent lens element 1() provided with an opaque covering 37 having a narrow slit 38 on the axis of the lens (see Figure 5). Magnets 25 and 34 may be supplied with energy through an oscillator 39 which is timed to energize magnet 25 once for each complete oscillation of lens holder 20 and to energize magnet 34 once for each complete oscillation of lens '31. 4

lVhen a subject -A--, either animate or inanimate, lis placedbefore the object glass and illuminated, its image will appear in the plane a-a at the front end lof lens holder 20 which oscillates `to scan the image from `top to bottom. This image represents thel subject matter to be transmitted and lens holder 20 is Wide enough to takein its full -width. Flat subject matter, such as pictures and papers, may be placed in `pla-ne a-a and be scanned directly.

Lens holder 2O is thin and lenses 21 and 22 very narrow so that onlyy a line of light' can enter the holder. All divergent rays are c reflected by lens 21 againstfthe inside walls 'allel rays pass into lens 22 from Which they' issue in a thin line or sheet, representing the varia-tions of light and shade in a line runlning horizontally across the image.

As lens 31 is vertical and disposed behind lens holder 20, slit 38 will intersect this sheet of light at right angles and allow a beam ot' light, as Wid`e as the slit and as thick as the sheet of light, to en ter the lens. The sheet ot' lightl beingv thin-and slit 38 narrow, it follows that but a point or pcncilof light, representing a small point on the image, can enterlens 31 at one time. As lens 31 oscillates, succeeding pointson the line or sheet of light enter slit 38 and form a continuous stream of light points or a pencil of light Whose intensity varies relatively to the lights and shadows on the line on 'the image covered by the end of the lens holder.

Lens holder 20 oscillates to move its front end from the top to the bottom', -or vice-versa,

of the image once for each likeness trans- I mitted and its speed is preferably such that likenesses of moving subjects may be transmitted, e. g. approximately sixteen likenesses per second.

In order to reproduce clearly, each likeness must be divided into fine lines and lens 31 must oscillate to cover the length of lens 22 once for each line. The image is thus disintegrated into lines by lens element 10 and the lines divided into points by lens 31. In effect, the transverse lines projected by lens element 10 are'turned by lens 31 and emerge parallel to the axes of the lenses in a pencil of light of varying intensity.

The pencil of light is directed by lens 31 into a photo-electric cell 40, which is connected in an electric circuit, and causes an electric current to flow therefrom which varies in strength in proportion to the intensity of the pencil of light. This current is passed through an amplifier 41 and a modulator 42 to transmitter 5 where it is impressed upon the carrier Wave and broadcast in the usual manner.

In order that a receiving apparatus, which will hereafter be referred to as a televisor, may be synchronized with a `transmitting station, which will hereafter be referred to as a transmitter, electric impulses are broadcast which Will control the oscillations of certain lenses in the televisor. For this purpose, neon tubes 43 and 44 or other suitable sources of light may be placed near photoelectric cell 40 and vconnectedin parallel with magnets25 and 34 respectively, so that, when a magnet is energized, one ofthe tubes will be illuminated and cause a strong synchronizing impulse to iow fromL the photo-electric cell. Thus, a synchronizing impulse is broadcast at the beginning of each oscillation of each lens element.

Referring now to Figure 6, the impulses, broadcast by the apparatus shown in Figure 1 and representing both sound and light, .are picked up by the radio receiver 50. The impulses representing sound pass through a filter 51 and are converted into sound waves `by a speaker 52 in the usual manner;

` The impulses representing light rays pass through a filter 53 to the televisor which has an amplifier 54 consisting of one orpmore stages of resistance coupled amplification. The plate of the 'last tube 55 of amplifier 54 is connected bya Wire 56 to one terminal of a light valve 57 whose other terminal is connected by a wire 58 to a 'source of energy 59 which supplies 'amplifier 54 with power; the output'of the amplifier' being controlled by a rheostat 60 connected in the filament circuit.

A lamp 61 is connected by Wires 62 and 63 to a suitable source of power, such as alightingv circuit, and the flow of current through reflector 65, placed behind lamp 61, directs .the lamp is regulated by a rheostat 64. A

the ,Karolus cell and be blocked by device 68,y

due to the relation of device 67 to device 68.

`When energized by the output of amplifier 54, the Karolus cell will produce a Kerr effect or rotate the polarized beam of light in proportion to the strength of the electric impulseV received. A pencil of light, Varying in intensity as the intensity of thepencil of light directed into the photo-electriccell in the transmitter varies, is thus permitted to pass through device 68. A lens 70, mounted- .for oscillation in the path of this pencil,

directs it into an oblong oscillating lens 71 'which directs it upon a screen or receiving surface 72 mounted at the focus of lens 71 and adjustable toward and from the lens by an adjusting screw 73. The televisor should be installed in a light-tight box and the light valve and lenses set into light-tight partitions. Receiving surface 72 may be a translucent screen, such as a ground glass plate, and be adjustably vmounted in the end of -the light-tiglit box.

If the surface 72 is in a vertical plane, lens 71 will have its axis of oscillation in a h orizontal plane and sweepits focus. in unison with lens holder 20 in the transmitter, vertically over surface 72 once for each likeness reproduced, while lens will have its axis of oscillation in a vertical plane and, in uni- `son with lens element 12 in the transmitter,

sweep its focus horizontally across lens 71.

` Photo-electric cells 74 and 75, shielded from light reflected from surface 72 by shields 76 and 77, are mounted adjacent surface 72 and connected to devices 78 and 79, such as Irelays or amplifiers, for increasing theoutput of the cells. lVhen magnet 25 is energized, the synchronizing impulse broadcast, due to the illumination of neon tube 43, is received and causes a strong beam of light to pass through the light valve. This beam is directed into cell 74 by the lenses,causiiig a` current to fiow which is amplified by device 78 and directed to a magnet 80 for oscillating lens 71. In like manner, when a strong impulse isbroadcast due to the energization of magnet 34, a strong beam of liglitwill be directed into cell and cause a current to fiow which is amplified by device 79 and directed to a magnet 81 for oscillating lens 70.

In orderV to oscillate` the lenses with one magnet each,` las shown in Figure 6, the lens elements shown in. Figures 8 to 11 maybe employed. Lens 70 is shown secured in a Vmounting 86 which is pivoted between two pointed screws 87 threaded through tlie'top and bottom of a frame 88 so that the lens may oscillate with a minimum of friction. 4Magnet 81 is securedto the frame and adapted to attract an armature 89 on mounting 86. A spiral spring 90, having one end secured to the mounting and the other to a pin 91 in the fraii'ie, tends to keep lens 70 oscillating when. it is once set in motion; magnet 81 'adding the necessary impetus once during each complete oscillation.

ln order to overcome any jerk which the magnet might impart to the lens and to make the -rateofvmovement practically uniform throughout each oscillation, a small dash pot 92 may' be secured to .the frame 'and its plunger 93 hinged to an arm 94 on mounting 86 opposite armature 89. .A

Lens 71 may be mounted on an a'xle 95 piv-` oted between pointed screws 96 threaded throughtlie sides of a frame 97 and magnet secured to the side of the frame with its armature 98 fixed on axle 95. A spiral spring 99 may have one end secured to a p in 100 in the frame and-its other end to the axle. A dash pot 101 may be secured to the frame and have its plunger 102 hinged to an arm 103 fixed on the axle. The lmagnet, spring and dasli-pot function similarly to those which control the oscillation of lens 70.

The modified arrangement shown in Figure 12 differs fromvthat shown in Figure 6 j only in that the lenses are `oscillated by two magnets each and a solenoid employed in the light valve instead of a Karolus cell.

rldhe iight valve 110 consists of a solenoid 111 ldisposed between light polarizing devices 67 and 68 and 4connectedto amplifier 54 by wires-56 and 58. l/Vhen amplifier 54 sends impulses through solenoid 111, a magnetic field will be set up wliiclrwill rotate a polarized beam of light in proportion to the strength of the impulses, thus functioning. in the -same manner as the Karolus cell pre- -v'iously described and permitting a beam of light of varying intensity to enter lens 70.

No details of the lens mountings have been shown, as the mountings shown/ in Figures 8 and 10 may be modified and provided with two magnets each and with one or two armatures. Lens 70 has been shown with an armature 112 substituted for arm 94, a magnet 113y provided for this armature and lexis 71 provided with a magnet 1144 placed on the opposite side offarniature 98 from magnet 80.

With this arrangen'ient, two magnets are employed for oscillating each lens element 1n the transmitting apparatus an lphotoelec tric cells 115, 116, 117 and 118 placed around surface 72. Magnets 81v and 118 are energized through the lagencies of cells 115 and 116 which are connected to the magnets through" relays or amplifiers 119 and 120, respectively. Magnets 80 and 114 are energized throughl lilo the agencies of cells 117 and 118 which are connected to the magnets through the relays or amplifiers 122 and 123, respectively.

Assuming that it is desired to broadcast a speech and the likeness of the speaker, he will be placed before the object glass, Well illuminated, the microphone positioned to catch the sound of his voice, and the transmitter put into operation.

Vhen the televisor shown in Figure 6 is not in operation, the spiral springs Will direct lenses and 71 toward photo-electric cells and 74. When the televisor is put into operation, lens 7 6 Will start tooscillate in unison With lens element 12, due to the illamination of neon tube 44 each time magnet 34 is energized but lens 71 will not start to oscillate until a. synchronizing impulse has been sent out due to the energization of magnet 25. As soon as this impulse is received, lens 71 will oscillate'in unison with lens elements 10 and 70 with lens element 12, thus synchronizing the televisor with thetransmitter.

The light from lamp G1 is allowed to pass through the light valve in proportion to the strength of the impulses which are in proportion to the intensity of the light reflected from the subject. Thus the likeness of the speaker is reproduced point by point upon screen 72 in exactly the same manner and at exactly the same time that the image of the speaker is disintegrated, point by point by lens elements 1() and 12.

It is apparent that the size of the image on screen 72 may be increased or decreased by moving the screen toward or from lens 71 and that the brightness of the image may be regulated by increasing or decreasing the light from lamp 61, as by regulating the current input with rheostat G4 or substituting a lamp of different candle power.

The embodiment of the invention as set forth above may be varied in numerous particulars `and various substitutions may be iliade, therein within the scope of the inven-.

tion as hereinbefore set forth Iandlhereinafter claimed.

le claim:

1. An apparatus for transmitting the likeness of subject matter includingr oscillating means for scanning the subject matter vertically and disintegiating the likeness into lines of light. oscillating means for disintegrating the lines of light into a series of 4points ot' light and directing thel points of light into aphoto-clectric cell to cause light regulated electric impulses to flow therefrom, y

means acting on the photo-electric cell to cause synchronizing electric impulses to HOW therefrom along with the light regulated impulses, and means for transmitting the impulses.

2. An apparatus for transmitting the likelens holder, means for oscillating the lens holder to lmove one of its ends over the space occupied by the subject matter, said lens holder embodying means to disintegrate light into lines, an oblong oscillating lens having its axis of oscillation at right angles to the axis of oscillation of the lens holder and Within the field of said lines, means for oscillating the lens and lens holder, a photoelectric cell mounted in the focus of the lens, means for illuminating the subject matter whereby light reflected therefrom will be directed into the photo-electric cell by the lens and cause electric impulses to flow from the cell, means for amplifying the impulses, and means for transmitting the impulses.

3. `An apparatus for transmitting the likeness of subject matter including a, lens holder, means for oscill ating the lens holder to move one of its ends over the space occupied bythe subject matter, an oblong oscillating lens having its axis of oscillation at i'ight angles means for oscillating the lens and lens holder..

a plioto-electric cell mounted in the focus of the lens, means for illuminating t-he subject matter whereby light reflected therefron'i will be directed-into the photo-electric cell by the lens and cause electric impulses to How from the cell, means for causing an additional impulse to flow from the photo-electric cell peroscillation of the lens holder, means for. causing an additional impulse to flow from the photo-electric cell per oscillation ot the lens, means for amplifying the impulses, and means for transmitting the impulses.

4. A televisor, for reproducing likenesses transmitted from a sending stat-ion as electric impulses, including means for receiving thc impulses, `an amplifier connected to the receiving means, a light valve connected to the amplifier, a lainp connected to a source oi'Y power, means for directing a beam of light from the lamp into the light valve, an oscillating lens aligned with the light valve, an oblong oscillating lens mounted in alignment With the first lens, a receiving surface mounted at the focus of the oblong lens, means for oscillating the first lens in one direction, and means for oscillating the oblong lens in the other direction.

5. A televisor, for reproducing likencsses transmitted from a sending station as electric impulses, including means for receiving the-impulses, an amplifier connected to the receiving means, alight valve connected to the amplifier, a lamp connected to a source of power, means for directing a beam of light from the lamp into the'light valve, an oscillating lens aligned with the light valve, an oblongI oscillating lens aligned with the first lens with its axis of oscillation at right angles to that of the first lens, a receiving surface mounted at the focus of the oblong lens, plioto-electric cells adjacent the receiving transmit-ted from a sending station as elec-po tric impulses, including means for receiving the impulses, an amplifier connected-to the receiving means, a light valve connected to the amplifier and consisting of a device for rotating a polarized beam of light disposed between a pair of light polarizing devices, a lamp connected to asource of power, means for directing a beam of light from the lamp into the light valve, an oscillating lens aligned With the light valve` an oblong oscillating lens aligned with the first lens, a receiving surface mounted at the focus of the oblong lens, means for oscillating the first lens iny one direction, and means for oscillating the oblong lens in the other direction.

,7. An apparatus for transmitting the likeness of a subject consisting of means for di. recting rays of light reflected from the subject through members having narrow elongated openings extending at right angles to each other and oscillatable aboutaxes parallel to said openings, into a photo-electric. cell, connected into an electric circuit, and means for transmitting the electric impulses emanating from the cell under the influence of the raysof light.

8. The method of transmitting the likeness of a subject matter consisting of scanning the subject matter to divide the light reflected therefrom into oscillating horizontal lines, scanning the plane of the lines to divide them into a succession of pointsforming a pencil of light, oscillating in a vertical plane directing the pencil of light in impulses into a photo-electric cell which is connected into an electric circuit directing further light into the photo-electric cell together with. that from the impulses incident to the scanning' operation, and transmitting the impulses flowing from the cell.

9. rllhe method of transmitting the likeness of subject matter consisting in oscillating an aperture element, which is as Wide as the subject matter, in a horizontal plane in close proximity to the subject matter to divide the reflection therefrom into lines of light through the aperture, oscillating element in a vertical plane to intercept the lines of light and divide them into a succession of points forming a pencil of light, directing the pencil of light together With the rays from another source into a photo-electric cell connected into an electric current transmitting the impulses flowing from the cell.

` l0. Themetliodof synchronizing a televisor having oscillating elements actuated by magnets, with a sending station, having oscillating elements consisting in transmitting an electrical impulse per oscillation, connecting each magnet to a source of energy con- -trolled liy aphoto-electric cell, receiving the impulses transmitted, converting the impulses into rays of light, and directing the rays of light into the photo-electric cells;

l1. The method of synchronizing an oscillating element in a receiving apparatus with an oscil ating element in atransniitting apparatus consisting in providing the transmitting apparatus with a photo-electric cell and a lamp, connecting the cell into an electric circuit, dashing light from the lamp into the cell at each oscillation of the oscillating element in the transmitter to cause electric impulses to flow from the cell, transmitting the impulses,- providing tlie receiving apparatus with a magnetic for actuating the oscillating element, providing the magnet with energy controlled by a photo-electric cell, directing a beam of light into a light valve, receiving the impulses, amplifying the impulses aud directing them to the light valve for causing light to issue therefrom and enter the photo-electric cell.

12. An apparatus for transmitting the to vcause light regulated electric impulses 'to flow therefrom, means acting on the photo-- electric cell to cause synchronizing electric impulses to flow therefrom along with light regulated impulses, and means -for transmitting the impulses, said lsynchronizing impulses being caused iiicident to lthe operation of both of the disintegrating means.

13. An apparatus for transmitting likeness of subject matter including means for scanning and disintegratingtlie image vot" the subject matter into a beam of light, electromagnetic means for operating said means to play the beam of light upon a photo-electric tube, means operable by the electro-magnetic means for playing additional light impulses on said photo-electric tube,l and means v for transmitting said impulses to a receiving j station.

light is directed, means for directing addif tional light impulses into said cell controlled by the actuation of each of said electro-magnets, and means for transmitting the imbeam so as to cause it to pass said obstructing means.

16. Apparatus for reproducing a likeness of subject matter at a distance, said apparatus including a transmitter and a televisor,

the transmitter *including a photo-electric cell, scanning means for disintegrating the light from the subject matter into light impulses and directing said impulses into said cell, electro-magnetic means for oscillating said scanning means, and light producing means operable incident to the operation of the electro-magnetic means for directing secondary impulses into said cell, means for transmitting the impulses from said cell, means connected with the televisor for receiving said impulses, said televisor including means for directing a beam of li ht to- Ward a receiving surface, means in uenced by said received impulsesA for varying the intensity of -said beam oscillatable means for spreading said beam on the receiving surface, and means controlled by said secondary impulses for causing the oscillation of said oscillatable means.

17. Apparatus for reproducing likeness at a distance comprising a transmitter and a televisor, the transmitter including spaced members each adapted to refract light in one dimension only and positioned with their majorI axes lat right angles, means to oscillate the members in synchronism, a member adapted to transmit variations otl light impulses as variations of electrical impulses, said transmitter being positioned to inter- 19.v In apparatus for reproducing likeness "at a distance, spaced interacting refractors adapted to retract light in one dimension only and mounted with their major axes at right angles, and means to oscillate the refractors upon their major axes synchronously. i

20. A radio television comprising means for transmitting impulses generated by the objects scanned, meanspto produce and transmit impulses supplemental to said scanning impulses, means to receive said scanning impulses, means to independently receive said supplemental impulses, means to employ said supplemental impulses, means to employ said supplemental impulses to maintain the receiving means 1n synchronism W1th the trans- .mitting impulses and means at the receiver to produce return impulses for maintaining the transmitting impulses in synchronism With the receiving means.

vIn testimony whereof We have signed our names to this specification. l

PHILIP CHALFIN. BENJAMIN CHALFIN.

cept light rays from one of said refractors, i

said televisor including a light valve Whose transmitting capacity is variable by the said electricalimpulses, a light receiving surface, a source of light directed toward said surface through said valve, and means to direct the transmitted li ht in synchronism with the oscillations of t e refractors of the transmitter.

' 18. In apparatus for reproducing likeness at a distance, spaced members a'dapted to refract light in one dimension only, said reractors being mounted with their major axes at right angles, means to oscillate one refractor to scan an entire image by progressive linear` areas and project the lines of light upon the other refractor,`a light responsive unit, and means to oscillate the second refractor in synchronism with the rstrefractor to project pencils of light upon said unit. i 

